Why is holly bad? Homesick English settlers probably brought it to Bainbridge centuries ago. It adapted well—too well! Holly spreads aggressively through roots and seeds, which birds eat and disperse in places like the Grand Forest, where it crowds out native plants such as trillium. It is terribly difficult to remove, even after just a few years of growth.
What to plant instead? There are many attractive hollies which are sterile hybrids and do not reproduce. Native Oregon grape also comes in many beautiful varieties that are decorative and hold up well in arrangements.
What should I do? Remove all English holly from your yard. Put seeds in trash, not compost.
Also, help on November 24, 26 and/or 27, 2021, in bundling branches from a cut-down holly in preparation for the public giveaway on November 27. See details here.